1. Field of Invention
The present invention relates to an optical module and a microscope.
2. Related Art
In recent years, optical microscope imaging technology has very impressive progress in image resolution, contrast and quality due to the excellent property of synchronizing radiated lights. In specific, a small amount of light radiation is able to obtain high quality optical microscope images and animations. Moreover, the microscope imaging technology with utilizing electromagnetic wave can be applied to not only the research and analysis of materials science, but also the biological and medical researches.
The conventional X-ray microscope is very large, so in some cases, it needs a container for overseas transportation. During the assembling of the conventional X-ray microscope, all actuator units and optical assemblies are individually fixed on an optical table (e.g. a stainless steal optical table). Since various actuator systems and optical elements have different shapes, heights and arrangements, the environmental temperature change may easily cause the thermal expansion issue of the X-ray microscope, thereby seriously affecting the measurement in nanometer scales and the positioning accuracy. For example, when the environmental temperature rises for 1° C., the expansion amount of a 1 cm3 aluminum cube in any of X, Y and Z directions is about 220 nm.
FIG. 1 is a schematic diagram showing one component of a conventional X-ray microscope, which includes an optical assembly 11 and a corresponding actuator unit 12 fixed on a stage 13. In this case, the optical assembly 11 is a pin hole element. The optical assembly 11 is disposed over the actuator unit 12, and the actuator unit 12 is disposed on the stage 13. The actuator assembly 11 includes an X-direction actuator element 121a, a Y-direction actuator element 121b, and a Z-direction actuator element 121c, which are overlapped along one direction. The actuator elements 121a, 121b and 121c can control the optical assembly 11 to move in the X, Y and Z directions, respectively. X ray passes through the center of the optical assembly 11 (the pin hole).
As shown in FIG. 1, when the environmental temperature is increased, the optical assembly 11, the actuator unit 12 and the stage 13 will have thermal expansions in the Z direction, which causes the optical assembly 11 (pin hole) to lift to a higher position (as indicated by dotted line). In this case, the shifting distance of the center of the optical assembly 11 (pin hole) is D. On the contrary, when the environmental temperature is decreased, the optical assembly 11, the actuator unit 12 and the stage 13 will be lowered along the Z direction, which causes the center of the optical assembly 11 (pin hole) to descend to a lower position. These undesired lifting and descending of all components will sufficiently decrease the measuring stability of the X-ray microscope.
Therefore, it is an important subject of the present invention to provide an optical module and a microscope that can ignore the environmental temperature variation and thus improve the measuring stability.